<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>盒子模型边框</title>

    <style>
        div {
            width: 300px;
            height: 200px;
            /* 边框宽度 */
            border-width: 5px;
            /* 边框样式 solid:实线 dashed:虚线 dotted:点线 */
            border-style: solid;
            /* 边框颜色 */
            border-color: pink;
            /* 边框圆角 */
            border-radius: 5px;
            /* 简写 */
            /* border: 10px solid red; */
            /* 指定上边框 */
            /* border-top: 5px solid pink; */
            /* 指定下边框 */
            /* border-bottom: 3px dashed red; */
        }

        .div2 {
            width: 200px;
            height: 200px;
            border: 2px solid blue;
            border-top: 5px dotted red;
        }
    </style>

</head>
<body>
    
    <div>1</div>
    <br>
    <br>
    <div class="div2">2</div>

</body>
</html>